Recreational vehicles are often supplied with three power sources, (1) a land line which is connected to the recreational vehicle to supply the vehicle with power from existing facilities at a campsite or the like, (2) a motor generator which is carried by the vehicle and which is normally operated from the same fuel source as the motor vehicle, and (3) an inverter which converts 12 volt DC battery power to 110 volt AC power. In the past, various systems have been provided for automatically operating motor generators and inverters which use sensing signals for detecting a load. However, the known prior art systems are not believed to fully account for all the various contingencies of operation of the various power supplies of a recreational vehicle to automatically connect and control the power supplies in a manner which will provide optimum convenience to the recreational vehicle user.
The present system is particularly suitable for use with a recreational vehicle using a generator powered by a stirling-cycle engine. Such generators are now being introduced to the recreational vehicle industry and are expected to substantially change the manner in which recreational vehicle motor generators are used. More particularly, the efficiency and low noise level of a stirling-cycle engine is conducive to much more extensive uses of the motor generator. For example, stirling-cycle motor generators may be used in circumstances in which motor generators heretofore would not be used due to the noise and cost of operation of same. As a more specific example, in quiet campsites and the like, it is generally considered impolite to indiscriminately operate a motor generator. However, with such stirling-cycle engines, the operation of a motor generator under those circumstances would not appear to be objectionable.
The power control and transfer system of the present invention is therefore well suited for use with stirling-cycle motor generators so that the capabilities of such generators can be fully exploited. The control system of the present invention is capable of switching between three available power supplies of the vehicle, the land line, the motor generator and the inverter to meet certain operating conditions and contingencies and to provide optimum convenience to the recreational vehicle user. As will be apparent from the Detailed Description Of The Preferred Embodiment, the system generally establishes a priority of use in the following order:
(1) land line, PA1 (2) inverter, PA1 (3) motor generator.